Alkaline fuel cells (AFC) are known as a fuel cell that operates at a relatively low temperature (for example, less than or equal to 250 degrees C.).
Various liquid fuels or gaseous fuels can be used in an AFC and for example, use of methanol as a fuel causes the following electrochemical reaction.Anode: CH3OH+6OH−→6e−+CO2+5H2OCathode: 3/2O2+3H2O+6e−→6OH−Overall: CH3OH+3/2O2→CO2+2H2O
In this context, Japanese Patent Application Laid-Open No. 2016-071948 proposes a solid alkaline fuel cell in which an inorganic solid electrolyte that exhibits a hydroxide ion conductivity is configured as a layered double hydroxide (LDH) that does not exhibit a liquid permeability and gas permeability.
LDH is expressed by the general formula [M2+1-xM3+x(OH)2][An−x/n.mH2O] (wherein M2+ is a divalent cation, M3+ is a trivalent cation, and An− is an n-valent anion).